A demand valve (100) for use in a breathing equipment is provided. The demand valve (100) comprises an actuating device (110) arranged to upon contact with water move a cover (111) from a first position to a second position, wherein the cover (111) in the first position allows ambient air to enter the demand valve (100) and the cover (111) in the second position prevents ambient air from entering the demand valve (100) thus allowing pressurized gas to enter the demand valve (100). A breathing equipment comprising the demand valve (100) and an immersion survival suit comprising such a breathing equipment is also provided.
